1. Field of the Invention
The present invention relates to a cutting apparatus appropriate for use in dicing semiconductor wafers, and more particularly to a blade cover encircling and protecting the blade of such a cutting apparatus.
2. Description of Related Art
FIG. 10 shows the cutting means 50 of a conventional cutting apparatus for use in dicing semiconductor wafers. The cutting means 50 comprises a spindle 52 having a rotary blade 53 detachably attached thereto, a spindle housing 51 for rotatably holding the spindle 52, and a blade cover 54 fixed to the spindle housing 51 on its front side.
The blade cover 54 comprises a rear cover part 55 fixed to the spindle housing 51, a front cover part 57 fixed to the rear cover part 55 with a bolt 56 to sandwich a rotary blade 53 therebetween, and a blade detecting means 60 detachably fixed to the top of the rear cover part 55 with a bolt 58. The fine positional adjustment of the blade detecting means 60 can be made with the aid of a fine-adjustment screw 59.
The blade cover 54 has a rear nozzle assembly 55a for flushing water to the rear side of the rotary blade 53 provided on its rear cover part 55 and a front nozzle assembly 57a for flushing water to the front side of the rotary blade 53 provided on its front cover part 57. As seen from FIG. 11, the blade detecting means 60 has light-emitting and light-receiving elements 61 and 62 confronting each other across the rotary blade 53 for detecting breakage in the rotary blade 53 if any, in terms of the strength of light falling on the light receiving element 62.
Inconveniently the rotary blade 53 cannot be removed and changed without loosening the bolt 56 and removing the front nozzle assembly 57a because of its interference with the rotary blade 53 in the way. Also, there is a fear of breaking the rotary blade 53 by striking the rotary blade 53 against the front nozzle assembly 57a when attaching or removing the front cover part 57.
Still inconveniently, the fixing bolt 58 must be loosened to withdraw the blade detecting means 60 up above from the rotary blade 53 for removing the rotary blade 53. Also, in cleaning the blade detecting means 60 the fixing bolt 58 must be loosened and removed to remove the blade detecting means 60. In fixing the blade detecting means 60 to the spindle housing 51 the fixing bolt 58 is driven and tightened, and then, the blade detecting means 60 is subjected to fine positional adjustment by using the fine adjustment screw 59.
Thus, the conventional blade cover requires a tedious and time-consuming work in removing and attaching the rotary blade 53 and the blade detecting means 60 to the spindle housing 51.